[PATCH v2 3/5] fs: fat: carve out fat_create_dir_entry()

[Heinrich Schuchardt]

fat_mkdir() and file_fat_write_at() use identical code to create a new
directory entry. Carve out a new function fat_create_dir_entry() to avoid
this code duplication.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
---
v2:
	handle errors returned by fat_create_dir_entry()
---
 fs/fat/fat_write.c | 93 ++++++++++++++++++++++------------------------
 1 file changed, 44 insertions(+), 49 deletions(-)

diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index 57522f96a8..ccdacd22c2 100644
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -1314,6 +1314,43 @@ static int normalize_longname(char *l_filename, const char *filename)
 	return 0;
 }
 
+/**
+ * fat_create_dir_entry() - create directory entry
+ *
+ * @itr:	directory iterator
+ * @basename:	name of file or directory to be created
+ * @size:	file size
+ * @attr:	file or directory attributes
+ * Return:	0 for success, -EIO on error
+ */
+static int fat_create_dir_entry(fat_itr *itr, const char *basename,
+				loff_t size, u8 attr)
+{
+	/* Create a new file */
+	char shortname[SHORT_NAME_SIZE];
+	int ndent;
+	int ret;
+
+	/* Check if long name is needed */
+	ndent = set_name(itr, basename, shortname);
+	if (ndent < 0)
+		return ndent;
+	ret = fat_find_empty_dentries(itr, ndent);
+	if (ret)
+		return ret;
+	if (ndent > 1) {
+		/* Set long name entries */
+		ret = fill_dir_slot(itr, basename, shortname);
+		if (ret)
+			return ret;
+	}
+
+	/* Set short name entry */
+	fill_dentry(itr->fsdata, itr->dent, shortname, 0, size, attr);
+
+	return 0;
+}
+
 int file_fat_write_at(const char *filename, loff_t pos, void *buffer,
 		      loff_t size, loff_t *actwrite)
 {
@@ -1383,8 +1420,6 @@ int file_fat_write_at(const char *filename, loff_t pos, void *buffer,
 		retdent->size = cpu_to_le32(pos + size);
 	} else {
 		/* Create a new file */
-		char shortname[SHORT_NAME_SIZE];
-		int ndent;
 
 		if (pos) {
 			/* No hole allowed */
@@ -1392,26 +1427,12 @@ int file_fat_write_at(const char *filename, loff_t pos, void *buffer,
 			goto exit;
 		}
 
-		/* Check if long name is needed */
-		ndent = set_name(itr, basename, shortname);
-		if (ndent < 0) {
-			ret = ndent;
-			goto exit;
-		}
-		ret = fat_find_empty_dentries(itr, ndent);
-		if (ret)
+		ret = fat_create_dir_entry(itr, basename, size, ATTR_ARCH);
+		if (ret < 0) {
+			log_err("Can't create directory entry\n");
 			goto exit;
-		if (ndent > 1) {
-			/* Set long name entries */
-			ret = fill_dir_slot(itr, basename, shortname);
-			if (ret)
-				goto exit;
 		}
 
-		/* Set short name entry */
-		fill_dentry(itr->fsdata, itr->dent, shortname, 0, size,
-			    ATTR_ARCH);
-
 		retdent = itr->dent;
 	}
 
@@ -1693,38 +1714,12 @@ int fat_mkdir(const char *dirname)
 		ret = -EEXIST;
 		goto exit;
 	} else {
-		char shortname[SHORT_NAME_SIZE];
-		int ndent;
-
-		if (itr->is_root) {
-			/* root dir cannot have "." or ".." */
-			if (!strcmp(l_dirname, ".") ||
-			    !strcmp(l_dirname, "..")) {
-				ret = -EINVAL;
-				goto exit;
-			}
-		}
-
-		/* Check if long name is needed */
-		ndent = set_name(itr, basename, shortname);
-		if (ndent < 0) {
-			ret = ndent;
-			goto exit;
-		}
-		ret = fat_find_empty_dentries(itr, ndent);
-		if (ret)
+		ret = fat_create_dir_entry(itr, basename, 0,
+					   ATTR_DIR | ATTR_ARCH);
+		if (ret < 0) {
+			log_err("Can't create directory entry\n");
 			goto exit;
-		if (ndent > 1) {
-			/* Set long name entries */
-			ret = fill_dir_slot(itr, basename, shortname);
-			if (ret)
-				goto exit;
 		}
-
-		/* Set attribute as archive for regular file */
-		fill_dentry(itr->fsdata, itr->dent, shortname, 0, 0,
-			    ATTR_DIR | ATTR_ARCH);
-
 		retdent = itr->dent;
 	}
 
-- 
2.36.1